cyoder4400

iTrader: (1)

Hey all, I have a 79 rx-7. Clutch master cylinder went bad so I ordered a new one through autozone. Come to find out, the one they supply has longer studs which don't allow it to tighten down as well and also the line fitting was a different size, so basically the wrong part but looked similar. I called around and found one for an 81 rx-7 with a different part number. Question is before I order it, does anyone know if the parts are interchangeable between years? The pics looked the same to my original part, but so did the first one...

Richard Miller

Not understanding the longer stud issue... but the 79-80 has a different pitch than the 81 on up. You rather need to find the right Master, or replace the hose and salve as well with the 81+

GSLSEforme

Op needs to find right m/cyl or find 10.0x10.-101.25 adapter. The too long stud issue from some suppliers has come up in the past. I double nut and remove studs from oe m/cyl and transfer to replacement,easy,peasy.

cyoder4400

iTrader: (1)

All great info, thanks. So if I am correct, I could get away with the 81 master but get a different line adapter that fits correct? Local shop has an 81 master cylinder and I was trying to get it finished by this weekend, hence why I'm trying to make the 81 work. Sorry if I am being ignorant on the topic, hydraulics aren't my specialty...

GSLSEforme

Take off clutch hard line,take with you to a parts place and get a section of line longer than enough to bend and form a duplicate replacement and with fittings on it to match threads in clutch m/cyl. This will be regular brake line and will be easy to match. Then take newly purchased line and clutch m/cyl to an automotive shop and have them bend the line to match AND reuse the fitting off of original hardline and flare it(like other end)so it will screw into flexible hose. What you are trying to do is match later model clutch m/cyl you have now with matching new hardline reusing one of the fittings from original line to mate with fitting on flexible hydraulic clutch hose now on car. Understand?

Swap studs out as recommended previously. The nuts necessary to do this are 8mmx1,25mm or you can use the original mounting nuts,install bleed and drive.

j9fd3s

iTrader: (3)

i ran into the longer stud thing with mine, its easy to pull the studs out and re-use the old ones, or just use bolts.

cyoder4400

iTrader: (1)

I ended up swapping the studs on the 81 cylinder. The line threads on the 79 were also jacked up from the store so that part was a no-go entirely.Only other part I could get quick was the 81. Swapped the studs and had to re-route the hydraulic line a bit since the 79 port is at an angle and 81 is straight up. All in all, it's in the car all bolted together. Will bleed the line tomorrow and hopefully everything holds up!